Knee brace



FIG. 1 is a perspective view of the front and right side of a knee brace; showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a right elevational view thereof;

FIG. 4 is a left elevational view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a top plan view thereof; and

FIG. 7 is a bottom plan view thereof. 

The ornamental design for a knee brace, as shown. 